Christmas often transcends such sorrow, no more so than on a frigid battlefield in Belgium in 1914, early in World War I. French and British troops hunkered down in their muddy trenches heard the sound of familiar carols, especially "Silent Night," from German trenches as little as 100 yards away. They peered through slits in their fortifications to see small Christmas trees, illuminated with candles, atop the parapets of the German positions. And there were signs: "We no fight, you no fight."